Chalermchai Pilapong

Smart magnetic nanoparticle-aptamer probe for targeted imaging and treatment of hepatocellular carcinoma

We report herein the development of a smart magnetic nanoparticle-aptamer probe, or theranostic nanoprobe, which can be used for targeted imaging and as a drug carrier for hepatocellular carcinoma treatment. The theranostic nanoprobe combines the delivery potential of a non-toxic cellulose derivative polymer, specific capability of cancer-specific molecule (DNA-based EpCAM aptamer) and the imaging capability of magnetic iron oxide nanoparticles. Our proof-of-concept design demonstrates efficient in vitro MR imaging of the cancer cells, and enhanced delivery of an anticancer drug into the cancer cells with comparable treatment efficacy.

Enhanced doxorubicin delivery and cytotoxicity in multidrug resistant cancer cells using multifunctional magnetic nanoparticles

Carboxymethyl modified magnetic nanoparticles (CMC-MNPs) have been designed as a vehicle for drug delivery in both drug-sensitive and drug-resistant cancer cells. We have demonstrated that the CMC-MNPs were able to load doxorubicin (DOX) with a high loading efficiency while also maintaining a good colloidal stability in an aqueous solution. According to a drug release study, DOX-loaded CMC-MNPs showed that the pH-dependent drug release property had a much higher release rate in acidic pH. Compared to free DOX, the DOX-loaded CMC-MNPs showed higher DOX accumulation in drug-sensitive cancer cells and much higher accumulation in drug-resistant cancer cells. These results indicate that our nanoplatform is highly efficient as a drug delivery system in both normal cancer cells and MDR cancer cells. In addition, the DOX-loaded CMC-MNPs can also enhance cytotoxicity against drug-resistant cancer cells in comparison to free DOX. The results obtained in this research demonstrate that our nanoplatform may be a promising approach in cancer chemotherapy and for overcoming multidrug-resistant cancer cells.

Silica gel-assisted solvothermal production of CdS, CuxS (x=1, 2) and ZnS with different morphologies

Abstract CdS, Cu x S ( x =1, 2) and ZnS with different morphologies were produced by the solvothermal reactions of M(CH 3 COO) 2 ·2H 2 O (M=Cd, Cu and Zn) and NH 2 CSNH 2 in hexane with and without silica gel as a hard template at 200 °C for 24 h. The product phases were detected using X-ray diffraction (XRD). Different morphologies were characterized using a scanning electron microscope (SEM). The existence of silica gel in modeling morphologies of the sulfides was characterized using Fourier transform infrared (FTIR) spectrometer. Raman spectra of different products show the vibrations at the same wavenumbers, although they are composed of different morphologies. Photoluminescence (PL) emissions of the corresponding phases with different morphologies are at the same values, but their intensities are increased by template adding.

Characterization and cellular studies of molecular nanoparticle of iron (III)-tannic complexes; toward a low cost magnetic resonance imaging agent

Herein, a new magnetic resonance imaging (MRI) agent based on molecular nanoparticles of iron(III)-tannic complexes (Fe-TA NPs) is reported. The paramagnetic and molecularlike Fe-TA NPs were successfully synthesized at room temperature within a few minutes without the use of any toxic agents or expensive equipment. The coordination states of the Fe-TA NPs were pH-dependent. The r1 relaxivity values of the bis-dominated and tris-dominated structures of the Fe-TA NPs were determined to be 6.31 and 5.24 mM-1 s-1, respectively, by using a Philips Achieva 1.5T MRI scanner. The Fe-TA NPs were 177 ± 12 nm in diameter (hydrodynamic size) with a zeta potential value of -28 ± 0.9 mV, dispersing very well in aqueous solution and were highly stable in phosphate buffered saline buffer (pH 7.4) containing competitive ligands and metals. From in vitro studies, it was evident that the Fe-TA NPs exhibited good biocompatibility, with high cellular uptake in HepG2 cells. Clearly, the Fe-TA NPs were found to induce signal enhancement in the T1-weighted image of the HepG2 cells. As a result, it can be stated that the Fe-TA NPs may have the potential for being developed as low-cost and clinically translatable magnetic resonance imaging agents in the near future.

Tannic acid (TA): A molecular tool for chelating and imaging labile iron

Abstract This report presents the potential utilization of tannic acid (TA) as a natural iron chelator. TA is capable of binding with small ferric complexes without competitive binding with endogenous iron‐containing molecules such as ferritin and transferrin. It was observed that the extracellular iron binding of TA resulted in the formation of self‐assembled Fe3 +‐TA complexes, which were then taken up by HepG2 cells via phagocytosis pathway with autophagy‐inducing properties. Obviously, TA was found to inhibit iron‐induced HepG2 cell growth. However, cellular interactions and biological responses to the treatment were found to depend on availability of iron. Based on the results of the iron efflux experiment, it can be stated that TA has the capability to mobilize iron from cells in the form of assembled Fe3 +‐TA complexes. Interestingly, TA‐mediated cellular iron influx and efflux were successfully monitored via MRI. The results of this study suggest that TA can be used as a molecular tool for chelating and imaging labile iron. This might be a promising approach for prevention and treatment of iron‐associated cancer or other iron overload disorders. Graphical Abstract Figure. No caption available.

Deferoxamine-conjugated AgInS2 nanoparticles as new nanodrug for synergistic therapy for hepatocellular carcinoma

Herein, a new nanodrug that exhibits multi-therapeutic modalities for synergistic treatment of hepatocellular carcinoma is reported. The nanodrug is composed of carboxymethyl cellulose modified silver indium sulfide nanoparticle (CMC-AgInS2 NP, served as a source of reactive oxygen species) covalently linked with deferoxamine (DFO, served as iron chelating agent). The DFO/CMC-AgInS2 nanodrug was taken up by the HepG2 cell and accumulated within the cytosol as well as the nucleus, leading to induction of cell arrest in the G2/M phase and subsequent apoptosis cell death. Compared to DFO, the DFO/CMC-AgInS2 nanodrug demonstrated better anti-proliferative activity against the HepG2 cell. As they were cultured in a medium supplemented with ferric ions, the HepG2 cells were induced to grow faster as compared to the cells without the addition of ferric ions. Fortunately, our nanodrug was found to inhibit the cell growth induced by ferric ions. Our results indicate that the nanodrug has synergistic effect for treatment of HepG2 cells via the intrinsic therapeutic property of CMC-AgInS2 NP and the iron chelating capability of DFO.

Large-scale synthesis of Sb 2 S 3 spikes by hydrothermal reaction

Spikes of Sb<inf>2</inf>S<inf>3</inf> (antimony sulfide) were synthesized by hydrothermal reaction at 100–200 °C for 6–48 h. By using X-ray diffraction (XRD), selected area electron diffraction (SAED), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), high resolution TEM (HRTEM) and UV-vis absorption spectroscopy, the products were specified as orthorhombic Sb<inf>2</inf>S<inf>3</inf> in the shape of spikes, with their growths in the [001] direction and E<inf>g</inf> of 5.40 eV. A diffraction pattern was also simulated, and was in good accordance with the SAED pattern obtained from the experiment.

Fabrication of novel ZnS/ZnAl 2 S 4 nanocomposite using a facile solvothermal route

Novel ZnS/ZnAl<inf>2</inf>S<inf>4</inf> nanocomposites were successfully synthesized via a surfactant-free solvothermal method using propylene glycol as a solvent. This method is mild, convenient, cheap and effective. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and photoluminescene spectroscopy techniques were used to characterize the ZnS/ZnAl<inf>2</inf>S<inf>4</inf> nanocomposites and the bare ZnS nanorods. The results show that the nanocomposites were built up from a zinc blend ZnS nanorod core and wurzite ZnAl<inf>2</inf>S<inf>4</inf> shell. Due to the PL spectra, the presence of ZnAl<inf>2</inf>S<inf>4</inf> shell on ZnS nanorod can dramatically change optical properties of the nanocomposites. In addition, the formation mechanism of the ZnS/ZnAl<inf>2</inf>S<inf>4</inf> nanocomposites was also discussed.